If you watched The Wire, you might think of "Omar", who steals from drug dealers. The bad guys love to hate him and the cops hate to love him.
Going to take off on this. Semi-spoilers.
Omar was a thief, a rough-and-tumble, intelligent and code-bound individual. His 'code' pretty much can be held to a mix of a.) Don't trust authorities, b.) Solve your own problems, and c.) It's all in the Game.
The Bad Guys have convinced this guy that the Party is the cause of some horrible thing that has happened to them, even tagging party members as being 'in on it'. Omar was an ambush predator, using disguises and cons to get into where he needed to be and then proceeding to lay out a very high level of firepower to deliver on his needs.
I think a Druid just sort of plays a weird spot there. But that is of course looking at my own perception as really I wanna do a Fantasy version of the Wire.
In essence I'm seeing either an Omar type or....
He plays way below his paygrade and could really become a thorn in the party's side at a later date. He's in it for the lulz as some have stated, but he also has an agenda that doesn't make itself immediately known. He's been a Good Guy but he's gotten so damned tired of the fight between Good and Evil, so tired of the constant pull between the two sides, and would rather have his own weird sense of control and manipulation as he moves forward. A complete bad-penny scenario, and is in it to win it.
Slainte,
-Loonook.